The present invention relates to an extended life, timed pinger for aircraft. On Mar. 8, 2014, about an hour after takeoff, Malaysia Airlines Flight 370 (MH 370) lost contact with air traffic controllers. Such contact was never regained and the flight never arrived at its destination in Beijing, China. A search commenced for the aircraft but numerous possibilities had to be contemplated.
Some scattered data was available to attempt to piece together where the aircraft may have gone including some satellite data periodically transmitted from the Rolls Royce engines of the aircraft. It was soon suspected that the aircraft had crashed into the Indian Ocean, which is a huge body of water more than a dozen times the surface area of the continental United States.
All commercial aircraft are fitted with black boxes that are designed to record flight data and cockpit voices. After an aircraft has crashed, the data from the black boxes must be recovered because it is crucial to an understanding of what precipitated the crash. Typically, these black boxes store the last several hours of data in a rolling fashion with the earlier data being erased as the later data is added. Once a crash occurs and a power supply to the black boxes is terminated, they have an internal power supply, typically one or more batteries, that operate to activate an audible signal such as what is known as a “pinger” which sends out a signal in the form of spaced audible tones and a fixed pre-set frequency. The typical frequency of the acoustic tones from a pinger is 37.5 kHz and, typically, battery life is about 30 days. The pings can be emitted every second or two and can have an initial source level of 160 dB at one meter range which provides a maximum detection range of 2-3 km.
The problem with this typical system for permitting detection of a downed aircraft is that the life of the battery providing operation of the pinger is typically limited to 30 days or so. In the case of flight MH 370, many of those 30 days were lost trying to figure out where it would be appropriate to search for the aircraft. At first, investigators thought the aircraft might be located east of Malaysia. Later, it was suspected that the aircraft had gone west into the Indian Ocean and then either north toward Pakistan or south over the Indian Ocean to a location well west of Australia, mainly somewhat uncharted territory outside the range of any radar surveillance that might have been able to pinpoint its location. While all of these investigations were underway, likely, the pinger on Flight MH 370 was “pinging,” draining the battery.
Even with the most modern battery technology, there is a limit to how long a battery may discharge enough energy to power a continuously operating pinger. As such, a need has developed for a system allowing searchers to be able to receive signals from a pinger beyond the usual 30 day lifetime of its battery system. It is with this need in mind that the present invention was developed.
The following prior art is known to Applicant: